Aiming is good, and being able to pick up new weapons works well. While obviously, the game needs some walk animations, what I'd want to see *first* are hit animations and effects - stuff that shows that you've been hit by enemies (other than just your health bar decreasing) and that you're successfully hitting enemies (other than them just disappearing).
It's weird, but you know you'll be able to do walk animations eventually - but hit animations change how a game *feels* so dramatically that putting them in early is really worth the time. It shows the player that what they're doing is working (or what they should avoid!).
Jump feels a little floaty, but that's just a matter of taste, and could be "right" if the character had a little jetpack or boots or something.